Air-brake apparatus



Aug. 301 l M. E. HAMILTON :lz-r AL Am BRAKE APPARATUS Filed oci. 7, 1926v e sheets-Sheet 1 ATTORNEYS 1,640,499 Aug 30'1927' l M -E. HAMILTON ET AL AIR BRAKE APPARATUS Filed Oct. '7I 1926 6 Sheets-Sheet 2 awww/ah.'

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FaZZ/elease and/ 35 lA Q Aug 30 927 M. E. HAMILTON ET Ag AIR BRAKE APPARATUS .INVENToRs e Maurice I Half/(H911 afg/mond i?. Hop/rms L ATTORNEYS Aug. 3o, 1927.. 1,640,499

M. E. HAMILTON ET AL AIR BRAKE APPARATUS led oct'. v, 192e e sheets-sheet' 4 /SMJQMM Aug. 3o'. 1927.

M. E. HAMILTQN ET vAL -AIR BRAKE APPARATUS A, INVENTORS Maur/ce E Hamiton lfai/mona' R Ha/rms ATTORNEYS Patented Aug. 30, 1927.

MAURICE E. HAMILTON, OF LA FAYETTE,

AND RAYMOND R. HOPKINS, OF WEST LA FAYETTE, INDIANA, ASSIGNORS TO AUTOMATIC STRAIGHT AIR BRAKE COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE.

AIR-BRAKE APP-AnATUs.

Application ined october 7,

This invention relates to improvements in air brake apparat-us in which the brake pipe volume is augmented'by a brake pipe reservoir, air from the brake pipe and trom the augmenting brake Apipe reservoir being ad mitted to the brake cylinder for service applications of the brakes. Anf emergency reservoir is provided and air from said emergency reservoir is admitted to the brake Cylinder for emergency applications of the brakes. Emergency reservoir air is also admitted into the brake pipe tor a quick release of the brakes. The control valve is operated to service position by a slow and moderate reduction of brake pipe pressure and operates to emergency position upon a sudden reduction of brake pipe pressure. An increase of brake pipe pressure operates the control valve to release position.

One ot' the objects of the invention is to provide means whereby the brake pipe auginenting reservoir pressure will not be reduced with the brake pipe pressure when the brake pipe pressure is reduced for an application of the brakes. Vhen the control valve is in service position the brake pipe air and the brake pipe reservoir air flow to the brake cylinder for a servicer application of the brakes.

Another object of the invention is to pro.- vide a service application valve and a separate and independent brake cylinder release valve, both of said valves being controlled by the same operating means and said operating means being subject to brake pipe, brake cylinder, and emergency reservoir pressures, and responding to variations in brake pipe pressure.

Another object of the invention is to provide means whereby the emergency reservoir air may be discharged into the brake piper tor a quick release of thebrakes, said means controlling the amount of emergency reservoir air discharged into the brake pipe.

Another object ot the invention is to provide a charging valve controlled by the opposed pressures of the brake pipe and brake pipe reservoir; and to provide means whereby said charging valve will control and operate a valve for retarding the release of brake cylinder pressure and will also operate a valve controlling the discharge of emergency reservoir air into the brake pipe forr a quick release of the brakes. l/Vhen operat- 1926. Serial N0. 139,989.

ing in retention release, ashereinafter de scribed,v the charging valve controls the discharge of air from the retention chamber of' the vdiaphragm structure, and thereby governs the'ratio of brake cylinder pressure built up in cycling operation.

Another objectv of the invention is to provide an emergency slide valve which will move only in response to an emergency reduction or brake pipe pressure. This. einer# gency valve remains stationary during all other operations of the control valve except that it moves -to vemergency lap position upon an equalization of emergency. prese.

sure in' the various chambers valve.

' There are many other objects and advantages oi the invention which will appear hereinafter.

In vthe drawings:

Fig. l is a diagrammatic view of a control valve constructed in accordance with this invention, the parts being shown in release and brake pipe reservoir charging position, the release govern-ing valve `being in quick release position. This is the non-overcharge position which results from an excessive rise in brake pipe pressure; I 1

Fig. 2 a view similar to Fig. l showing the,L parts inl normal charging position,.in which position the emergency reservoir and the brake pipe reservoir are charged at the same'time. This position results from a normal rise in' brake pipe pressure during the charging ,operation Fig. 3 a view similar to Fig. l showing the. partsin service application position;

Fig. 3 a detail sectional view otl the service application valve in service position;

Fig. 4t a detail view of the service application valve in service lap position;

i Fig. 5 a diagrammatic view of a portion ofthe control valve showing the parts in graduated release position;

Fig. 6 a view similar to Fig. 5 showing the vparts in retention release position;

Fig. 7 a view similar to Fig. l showing the parts in emergency application position;

Fig. 8 a view similar to Fig. 7 showing the parts in emergency lap posit-ion;

Fig. 9 a diagrammatic View of the apparatus; and Y Fig. 10 a detail vien7 of the service valve provided with a service lap spring.

of the. control V charge position.

In order to simplify the description of the control valve, the various parts and the ports and passages Will not be specifically described except in connection with the various operations ot the valve. v

ln the diagrammatic viev*` 9, fr .designates the control valve, B the brake cylinder, C the brake pipe, D the service reservoir, E the emergency reservoir and F the quick action reservoir.

A control valve constructed in accordance With this invention comprises an emergency slide valve a, a service application valve Z), a release valve e, a charging' valve CZ, a quick release control va'lve e, and a manually operable release governing valve The emergency slide valve moves only in response to an emergency reduction of brake pipe pressure and movesd to emergency lap position upon an equalization ot emergency pressure in the various chambers of the control valve. In all other operations of the control valve the emergency valve remains stationary. The service application valve and the release valve are operated by a diaphragm structure in which the diaphragm are subect to brake pipe, brake cylinder and emergency reservoir pressures, the diaphragm structure responding to variations in brake p'pe pressure and the application valve and the release valve performing their functions independently ot each other. T he charging valve controls the charging of the system. This valve has a normal charging position and a non-over- The non-overcharge position results from an excessive rise in brake pipe pressure and in thisposition the brake pipe reservoir alone Will be charged. ln the normal charging positionot this valve the brake pipe reservoir and the emergency reservoir Will be charged simultaneously. rThe quick release control valve controls the amount of emergency reservoir air dumped into the brake pipe 'for a quick release of the brakes. lThe manually operable release governing valve has three positions, a quick release position, a graduated release position and a retention release position. ln the quick release position it provides for a full quick release of the brake cylinder pressure and in its graduated release position it provides for a sloivv release of brake cylinder pressure. ln its retention rele-ase position it provides for building up brake cylinder pressure during cycling operations.

The control valve is provided with a main valve chamber 1 in which is arranged the emergency valve c. rlfhe chamber 1 is formed at one endl With an emergency piston chamber 2 in Which is arranged a large emergency piston 3. At its other end the main valve chamber is formed With a small chamber 4 in which is arranged a supplemental piston 5. Connected to the piston 3 is a '-9, there lbeing a slight lost motion betiveen the valve and these flanges, for a purpose which Will hereinafter appear. The piston 8 serves as a movable abutmenty which separates a quick action Vchamber 10 from the main valve chamber. The quick action reservoir F is connected directly to the quick action chamber.

The service application valve is'V connected by a lever11 to thecentra'lstem 12 ot the diaphragm structure. The release valve e is connected to said central stem by a lever 13. 'The diaphragm structure comprises an actuating diaphragm 14;, an equalizing diaphragm 15, and an emergency diaphragm 1G.`

Between the actuating diaphragm and the wall ot the valve casing is formed an actuating chamber 17; between the actuating diaphragm and the equalizing diaphragm is formed a brake cylinder chamber 18; between the equalizing diaphragm and the emergency diaphragm is formed a retention chamber 19 and between the emergency diaphragm and the adjacent `Wall ot the valve casing is formed an emergency reservoir chamber 20. he levers 11 and 13 and the release valve. e are all arranged in the brake cylinderchamber 18. 'lhe brake cylinder B is connected directly to chamber 18.

The charging valve (Z is connected to a lever 21 and said lever is operatively connected to a charging diaphragm 22. diaphragm 22 separates a brake pipe reservoir chamber 23 from a 'charging chamber 24, said chamber surrounding the 'charging valve and forming a charging valve chamber.

yEhe release control valve e is mounted in a chamber 25 and is operatively connected to the piston stem 2G of the release control valve piston 27. rllhe piston 27 is mounted in a chamber 28 and the piston stem 26 eX- tenes through smalllequalizing chamber 29. The release governing valve f is connecte-d to a. manually operable rod 30 by means of which the valve may be set in any one of its three. positions. The release governing valve is mounted in a release governing valve chamber 31.

llllhen charging, the system air passes from the brake pipe into a small chamber 32 above an Vemergency brake pipe vent valve 83 and lioivs through passage 3e into chamber 4 in front ot the supplemental piston 5. From The' chamber 4 air will low through groove 35 around the piston 5 and into the main valve chamber 1. The air flowing into chamber 4 will :torce the supplemental piston and the emergency piston toward the right, as viewedin Fig. 1, until the stop pin 3G contacts with the wall of the quick action chamber 10. rlhis will arrest the supplemental piston, the emergency piston, and the emergency slide valve in their normal charging positions. A small chamber 37 is connected to the main valve chamber by a port 38 said port being uncovered when the main emergency piston 3 is in its normal or charging position. 1n the chamber 37 is mounted a non-overcharge valve 39 said'valve being in the ,torni of a` piston arranged to reciprocate in said chamber. Aroundv said piston is formed a normal charging groove 40 and through said piston is formed a restricted charging port 41V. A. spring 42 normally holds the valve 39 raised to uncover or open Y the charging port 43 which opens into the quick action chamber. The quick action reservoir F is connected directly to the chamber 10 and receives its charge therefrom. Vihen the rise in brake pipe pressure is rapid, or excessive, the pressure vbuilds up on top of the valve 39 and forces it downward against the tension lot the spring 42 and seats said valve, thereby closing the charging groove 40. Air will then pass through the restricted charging port 41 to the chamber' 10 and to the quick action reservoir. By this means an overcharge of the quick action reservoir is prevented. Brake pipe air will pass from chamber 1 and chamber 2 through passage 44 into the actuating chamber 17 ot' the diaphragm structure. Passage 44 is connected by passage 45 to the release governing valve chamber 31 so that brake pipe air will .ilow into said chamber. rlfhe actuating chamber 17 is connected by a passage 46 to theservice application valve chamber 47 so that the brake pipe air will flow from chamber 17 directly into the application valve chamber. ln the passage 46 is arranged a non-return check valve 48 to prevent air flowing from the valve chamber 47 back into the actuating chamber.

TWhen the emergency valve ci is in its normal or charging position it uncovers a charging port 49 in the main slide valve seat and this port is connected to the charging chamber 24 below the diaphragm, 22 by passage 50 so that brake pipe air will flow into said chamber. It is to be noted that the charging chamber surrounds thev charging valve CZ. The rising pressure under the diaphragm 22 will raise said diaphragm until it engages the normal charging stop 51. This stop is held in itsnormal -charging position by a spring 52, said spring being or' sullicient tension to hold the diaphragm in normal charging position under arise of brake pipe pressure at a normal charging rate. An excessive rate of rise of brake pipe pressure will orce therdiaphragm upwardly and compress the normal charging stop spring and thereby move the charging valve into non-overchargeposition. This is the position shown in Fig. 1. rl`he charging diaphragm is pivotally connected to the lever 21 and one end of said lever is operatively connected to the charging valve, its other end being pivoted -on a suitable post in the charging chamber so that the upward movement of the charging diaphragm moves the charging valve upward vinto charging position. ln its non-overcharge position thecharging va ve uncovers the brake pipe that brake pipe reservoir pressure will be present in said chamber. When the pressures in chamber 23 and in the charging. chamber 24 have equalized,'or substantially so, the spring 52 will iorce thediaphragm 29. downwardly and move the charging valve to normal charging'position (F ig. 2). ln' the 'non-overcharge position of the charging valve, as shown'in Fig. 1, the ,brake pipe reservoir alone will be charged and no air will pass to the emergency reservoir.

PeZease-Bra/c'e pipe reservoir and emergency reservoir charging-Normal chargng position (Fig.

`When the brake pipe pressure is raised at a normal charging rate the .charging diaphragm 2Q. will be raised until it contacts with the normal charging stop 51. This will move the charging valve into the position shown in FigLQ in which position a charging port 58, through said valve, will be connected by branch ports to a brake pipe reservoir charging' port 53a and to an emergency reservoir charging port 59. Port 53 is con nectcd to passage 53 which leads to the brake pipe reservoir D, as hereinbeore described.

Port 59 is connected to a passage GO which leads to the emergency reservoir E. In the passage 60 is a non-return check valve 61 which prevents a back 'flow ot air trom the emergency reservoir to the charging chamber 24. The emergency reservoir charging passage 60 is connected by a branch passage 10:2 to the quick release control chamber 25.

'In said passage is arranged a check valve 103 which seats toward the passage 60 and prevents the flow ot air from chamber 25 lli into passage-60 but permits emergency reservoir air to iiow into chamber 25. ln the seat ot the release control valve c is formed a port 105 and said port is connected by a passage 104: to the emergency reservoir chamber 20. ln the graduated release and in the retention release positions or the release governing valve the port 105 is always open to chamber 25 so that chamber 20 will be charged at the same time and at the same pressure as the emergency reservoir. ln the quick release position oi the release governing valve the chamber 2O will be charged during the rise ol brake pipe pressure and will be Yfully charged to emergency reservoir pressure when the quiclr release control valve ance of n c assumes normal running position with the pressures equalize-l on opposite sides or the piston 2T and port 105 slightlyopen. 'lhe movement or the piston 27 and the valve c are hereinafter fully described under the heading"llelease alter service-Quick release. Y

rlhe charging valve will remain in this double reservoir charging position and there will be an `equalization or' pre lnires in all the reservoirs. The spring el@ will litt the non-overcharge valve 89 and permit the charging olf the quiclr action reservoir through the charging groove Llll and the charging port d3 at a normal rate. rlChe pressures on opposite sides oit' the charging diaphragm 22 will equalize and the charging valve will remain in normal charging position until there has been a change in the balssures in the chambers 2d and 23 on opposite sides olf the charging diaphragm 22.

Service application (Fig.

A reduction ot brake pipe pressure permits' air to flow from chamber 1'4" above diaphragm 14: and from chamber 24 beneath diaphragm 2Q, through passages lll and 50 respectively, through chamber 1 and groove 35, chamber 4l and passage 34' to the brake pipe thence to atmosphere through the engineers brake valve; pressure in quick action reservoir chamber 10 liows into chamber 2 through port d3, groove fr0, chamber 3'?, and port 88 so that the pressure in chamber 10 is maintained equal with the brake pipe pressure in chambe 2 and the emergency piston 3 and the valve a will remain stationary. Check valve 61 prevents emergency reservoir pressure from iiowing into chamber 9A. lralre pipe reservoir pressure is prevented lroin flowing into chamber 24- by checlr va ve and is prevented from lio ving into chamber 1'? by check valve d8.

As soon as the pressure in chamber 17 above diaphragm 14C begins to reduce, emergency reservoir pressure in chamber 2O under diaphragm 16 will force the diaphragm assembly 16, 15, 14 upward and through the medium of lever 13, force the release valve c downward closing communication between bralre cylinder chamber' 18 and ati'nosphere, while at the same time application valve Z) will be, through the medium of lever 11, forced downward to establish communication from chamber i-T through port o2 in application valve Y). and port 63 in its seat, to chamber Y18 and the brake cylinder.V i

rllhe brake pipe reservoir chamber 55 is connected tothe application valve chamber A? TEW sage is a checl; valve rais check a. ve is in chamber All aneseats toward the chamber and when closed prevents air passing from charmer/5i" to chamber 55 so that during the Vchargi L, ope* ation brake pipe air cannot flow `from chamber 4'? into the brale pipe reservoir l). in' the chamlicr and surrounding the stem oi' the valve {it} isv a spring t3?, said springliolding the valve (El) on its seat. rl`he check valve provided with a depending tubular soclret 68 iu which i perates the headed upper end 69 t Vthe valve stem 5;, said .socket providing tiexible or lost motion'coimection between e stem Gli a d the valve ihen the ap- Vnication valve is moved downwardly to fon position the port 62 will be t into communication with the port 63 n its seat. As soon as the ports G2 and "B are in communication brake pipe air from chamber if? and chamber 1'? will flow into the brake cylinder chamber 1S and into the bralre cylinder. This will result' in a local reduction of brake pipe pressure which will increase the speed or' the serial action of the control valves throughout the train. 'l

continued downward movement of the application valve to lull applica Yion position scat,

will' pull the checl; vz"Y from its slightly compressing the spring 6T the check valve GG is unseated reservoir air will ilow into chan thence to the brake evlinder. 'n' I Y. l sures in chambers 17 and are ecual brake pipe air and brake pipe escivoir air "il iiow together to chamber 1S and therce to the brake cylinder.

The equalising diaphragm is larger in diameter than the actuatii diaphragm and the emergency diaphragm in order that the desired brake cylinder pressure will built up in the bralre cylinder betore the service application valve is moved to lap position, as hereinafter described. Vlhe degree oit brake cylinder pressure developed Vfrom a given brake pipe reduction will Adepend upon the relative effective areas oi' the. diaphragme. rEhe service application valve will remain in service position until the pressure in chamber 18 is such that the downward 'torce eX- erte'd on the diaphragm 15 plus the torce eX- through the passage y `(lmitrolling this il l) lili) erted on diaphragm 14 by the pressure remainingin the actuating chamber 17 is sufficient to overcome the undisturbed emergency reservoir pressure in chamber 20. It is desirable that the brake cylinder kpressure be developed at av ratio of two-and-one-halt tov one ot' brake pip-e*reduction` so that upon a ten pound brake pipe reduction a twentyiive pound brake cylinder pressure will bc developed before the service valve is moved to lap position. This ratio may be varied by varying the effective area of the diaphragm 15 asv compared wit-li the effective areas of the diaphragms 14 and 16.

socket of the check valve 66, as shown in Fig. 10, said spring serving to assist the lapping of the service valve when the desired brake cylinder pressure is in chamber 18. rThis spring may be a very light spring and will not interfere with the movement ot the service valve Z2 to service position under a service reduction ot brake pipe pressure. The spring` 150 will lap the service valve with a slightly lower pressure in chamber 18 than would be necessary with the valve operating without the spring 150. The release valve will move in response to the movements or the .diaphragms but that movement will not be sufficient to cause the release valve to assume release position and the release ports will remain closed. ln the lap posisition of the service valve the check valve 66 will return toits seat as shown in Fig. 4.

lf it be desired to increase the Abrake cylinder pressure a further reduction of brake pipe pressure is ma'de and the application valve will again move to service application position and the brake cylinder pressure will be built up in direct proportion tothe second brake pipe reduction. rlhe brake cylinder pressure may thus be built up step by step until'there is an equalization of pressures in the brake pipe reservoir, brake pipe.V and brake cylinder. It will, oi course',A be understood that upon a proper brake pipe reduction a. full service braking pressure may be developed in the brake cylinder in lre-V sponse to a single brake'pipe reduction. A

Should the developed brake cylinder pressure leak down below the desired brake cylinder pressure theV .emergency reservoir pressure in chamber 20 willv move t-he diaphragm structure upwardly and again place the-ser'vice Lvalve in service position. It 'the reduction oi' brake cylinder pressure through' leakrlhe servicel valve will remain in service position untilv ment lor' the service valve to full service position the service ports 62 and 63 will' bc brought into partial register and bra-'ke pipe air will ilow from chamber 47 and from chamber 17 to the brake cylinder. It the service valve is moved tol full service position the valve 66 will be vunseated and air from' the brake pipe reservoir and the brake pipe will flow to the brake cylinder to compensate lor leakage.

Vhen the brake pipe pressure is reduced for a service application of the brakes the pressure in chamber 24 below the charging diaphragm 22v will be reduced at thel same time and at the same rate. As soon as this reduction begins the diaphragm 22 will be moved downwardly by the pressure in chamber 23 and the charging valve'al will be moved to its lowermost position and. communication between the chamber 24 and the service reservoir and the emergency reservoir will be closed.

Release @fier service-Umirol oai/ve in. Quick release position (Fig.

The control valve is adjusted for quick release operations by moving the release gov-` erning valve to quick release position, as shown in Fig. 2. The release'of brake cylinder pressure is eectedfby an increase of Vbrake pipe pressure through the manipula-j tion of the engineers brake valve, in the usual manner. The increase in brake pipe pressure results in a corresponding increase in pressure in the actuating chamber 17 and 1in the charging chamber 24. The increasing pressurein chamber 17 forces the diaphragmstructures 14, 15 and-16 downwardly and the levei13 will move the release valve to release lposition and the lever 11 will move the applicationr valve7 but this movement of the application valve will be an idle one. The lost motion connection between the valve stem 64 and the check valve 66 will permit the application valve to move upwardly without disturbing the valve 66. The portsjof the application valve will be closed, as shown in Fig. 2.

The release valve cis formed with two re lease ports and 71. Port 70 is the quick release port and port 71 is the graduated release port. Port 7 0, whenthe release valve is in release position registers with a port and passage 72 which leads to a port 73 'in the seat ot the release governing valve Thev release governing valve is formed with a' groove 74 which in the quick release position of said valve connects port 7 3 with the port: 75. Port 75 is connected by a passage 76 to aI chamber 77 so that brake cylinder pressure may flow` from chamber 18 into said chamber" when the release Vgoverning valve is in' quick yrelease' position.'V The chamber 77 is connected by' a `passa-ge 78 to Y "a large atmospheric port 79. Passagev 78 is controlled by a check valve 8O which seats toward vthe atmospheric port. A small port 81 is formed through the check valve so that when said valve is seated brake cylinder pressure may slowly blow down through said port 8l 'to atmosphere when the release valve is in release position. The check valve 80 is connected by a stem to a piston 82, said piston reciprocating in a chamber 88. A.

spring 8a holds the check valvev 8O away from its seat so that the chamber 77 is open directly t@ the atn'iospheric port 7 9 thus permitt-ing brake cylinder pressure to tlow from passage 76 directly to atmosphere through port (9. rthe passage 72 is connected d1- rectly tothe passage 76 through a small leak port or restriction port 85, said leak port functioning more particularly in the graduated release position ot' the release governing valve, as will be `fully hereinafter described.

The graduated release port 71, in the release position or the release valve c registers with a port and passage 86, said passage leading to a, port 87 in the-release governing valve seat. ln t-he quick release position or the release governing valve port 87 is closed thus rendering` the graduated release port 71 ineffective in the quick release position of the release governing valve.

The pressures in chambers 23 and 24 will be substantially equal when the service valve Z9 has been moved back to lap position and, as hereinbetore stated, the charging valve will be in its lowermost position, as shown in Fig. 3. rlhe increasing pressure in chamber 24l will movethe diaphragm 22 upwardly to normal charging position, the spring pressed stop 51 holding it in that position so long as the brake pipe pressure is increased at a normal charging rate. The chaiging valve will be moved upwardly to charging position, as shown in Fig. 2. Port 58 will register with port 53ZL and withr port 59. Brake pipe air may then flow :trom chamber 24 through port 58, port 53, and passage 54C to the bi-akepipe reservoir. It will also flow through passage 57 into chamber 23. Check valve G1 will be held to its seat byV emergency reservoir pressure and there will be no liow of air from chamber 24 to the emergency reservoir. v rlhechamber 83, above the piston 82, is conn nected by passage 88 to a port 89 in the seat oft the charging valve. Port 89 is connected by groove 90 in the charging valve to an atmospheric port 91 so that Jthe chamber 83 is connected to atmosphere and the spring 84 will hold the valve 80 in open position.

The charging'valve Ais formed with a port `and oassae'e 92 which obensinto the chamber 24' through a port 93'. Port and passage 92 94 and saidV passage leads to aport 95V in registers with a port and passagev the quick release position of the release governing valve a cavity 96 connects port 95 with a port and passage 97. and said passage leads to the piston chamber 28 or' the quick release control valve e. In

the charging position of the charging valvel l air will ilow from the charging chamber 24 through port 93, passage 92, port and passage 94;, cavity 96 and passage 92" into chamber 28. rlhe rising pressure inchamber 28 will torce the piston 27 inwardly, or toward theV right, as viewedin 2, and will move the quick release control valve e to quick release position and will uncover port 98. Port 98 is connected by passage 99 to a port 100 in the seat oi? the release governing valve. in the quick release position of the release governing valve, port 100 is connected by port'101 toV ation but permitting emergency reservoir air to flow into the chamber 25. lV hen the port 98 is uncovered emergency reservoir air vill low from chamber 25 through port 98 and the connected ports and passages into the brake pipe iior a quick release oit' the brakes.

The emergency reservoir chamber 20 oit the diaphragm structure is connected by passage 104; to port 105 in the seat of the quick release control valve c. The valve e is piovided with al cavity 106 which in the release position ot said valve connects'port 105 to an atmospheric port 107 so that chamber 20 will be vented to atmosphere so long as the valve e remains in its release position.

ByV

venting the chamber 2O to atmosphereth'e diaphragm structure will be given a rapid downward movement 'to quickly vand posi.- tively move'the valve c to release position. rihis will make the movement of said valve to release position very sensitive for the reason that a slight rise ofV pressure in chamber 24 will move the charging valve to charging position and this will bring about the venting of chamber 20 to atmosphere.

When the piston 27 is forced inwardly, the inner end oit its stem 2G engages aspringpressed stop 108 and forcesv it inwardly until the stemA abuts vagainst a rigid stop. This movement places the valve c in its quickfrelease position, as shown in Fig. 2. Around the piston 27 is formed an equaliZing-groove 109, said groove being open around the piston when the piston is in its inner position,

iis

thereby o Jenin@` Jort 105. rrhis movement ot the pis- Y ton 27 partially closes groove 109, leaving said groove slightly open into chamber 28. In thisposition ott-he quick release control valve emergency reservoir air may flow to Chamber 20 and the floiv of emergency. reservoir air tothe brake pipe, through chainber 31, is stopped. The chamber 20 is of small volume and the groove 109 is ot considerable capacity so that the equalization ot pressures in chambers 29 and Q8 will take place in a comparatively short time. llfhen the piston Q7 has been moved back to partially close the groove 109 the pressures will equalize on opposite sides ot' the piston 2T during any rise ot'bralre pipe pressure in chamber 28 Which taires place at a normal charging rate, and the pressures Will therelore be n'iaintained at an equilibrium on opposite sides ot the piston without further movement oi the valve c to release position. 1t the brake pipe pressure is suddenly increased any considerable amount, such as would result t'rom a hielt-olif movement of the engineers brake valve, the piston 2T will again be forced inwardly against the tension ot the spring-pressed stop 108 and the port 08 Will be again uncovered aud the chamber 20 will be again connected to atmosphere. The pressures Will quickly equalize on opposite sides oi the piston 2T and the stop Will again move the valve e bach to lap position and port 08 again will be closed. When the system is tally Ycharged the charging valve remains in its normal charging position, as shown in Fig. 2, with all ot' the reservoirs and chambers charged to running pressure.

l/Vhen the brake pipe pressure is increased rapidly and at a rate greater than the normal charging rate, the rapid increase in pressure in chamber 24 forces the diaphragm 2Q upwardly and moves the normal Acharging stop 51 upwardly and compresses the normal stop springl 52. rllhis additional upward movement ot the diaphragm 22 movesv the charging valvefiuayvardly into its no i'- overcharge position, as shown in ln this position oit the charging valve.y port 98 is in register with port 89 sothat air may flowv from the charging. chamber intothe chamber 83 on topA or' the piston VS2 thereby forcing ti valve 80 to its seat.

e This cuts oft the free escape or brake cylinder pressure andvsolong as lvalveis held seated brake cylinder pressure will iioiv tothe atmospheric port through the restricted release port 81. As soon as the pressures on opposite sides oi diaphragm 22 have equalized the charging valvewill be moved into normal charging position by the normal stop spring 52 and chamber 83 Will then be vented to atmosphere and the valve Willvbe movedto open position and thereby permit the tree exhaust ot brake cylinder pressure through port 79. 1n the 'non-overcharge position vot the charging valve port and passage 92 will ren ain in communication with port 04e so that theoperation ot' the'quiclr release control valve Will be the same as when the charging valve is in its normal chargingr position.

il/Then bralre pipe pressure is reduced for an application oi the'bralres the pressure in chamber 23 moves the charging valve down- Wardly to thelimitot its movement, as described under the heading Service application. ln this loW-ermost position ot the charging valve port 941 is'connccted to at# mospheric portr91' through a. cavity 110 in said valve; This vents chamber 28 lto atmosphere and the pressure trapped in chamber 29 Will torce the piston 27 and the valve e to the limit oi" its movement toward the lett, as viewed in Fig. Q. In this position of the valve the chamber 29 Will be connected to atmospheric port 107 kby the groove 100 in valve e so that both chambers .2 and 20 vvill be'vented lto atmosphere during an application ot' the brakes Y ln the quick release position ot the release governing valve cavity 112 connects port 113 toatmospheric p o'rt 113. Port 113 is connected. y passage 11aL tov port 115 in the seat ot the-emergency `slide valve. The emergency sli-de valve is pr'ovioetl With a cavity 110 ivhich, in the normal or inactive position oit said valve, connects port 115 to a port 117." This latter port is connected by passage 118 tothe retention chainber'19 so that in the quick releasek operations ot' the control valve the retention chamber is at all times, except in emergency applications, vented to atmosphere.

ReZease after] service-Graduated release (Figo). Y

is moved to connect Dort rand passage 97 to' atmospheric portv 111. This places chamber 2S in direct.communication lwith atmosphere. Port is closed.V This prevents air llowing tothe chamber 28, thus rendering the quick release control; valveinoperative and preventing' the release of air from chamber 20 in graduated release operations. The pressure in chamber 20, theretore, will remain constaut with the emergency reservoir pressure. Cavity 711 is moved out of register with port 75, thereby closing port 7 5 and shutting oil the tree exhaust ot brake cylinder pressure with porc 100 and port 100 is closed. This prevents the lo-w of brake pipe air :trom chamber 31 to chamber 25 and also prevents the irlo'w of emergency reservoir air from chamber 25 to chamber 31. Cavity 112 in the release governing valve, in the graduated release position of said valve, as well as in the quick release position of said valve, connects port .113 to the atmospheric port 113a so that the retention chamber 19 will be vented to atn'iosphere during graduated release operations. 1n the graduated release position of the release governing valve, port 87 remains closed so that there can be no release of brake cylinder pressure through the release port 71 ot the release valve c. -When the release valve c is in release position brake cylinder pressure may slowly blow down through port 70, passage 72, restricted release port 85 and thence through passage 7 6 and chamber 77 to the brake cylinder exhaust porty 79. In all other respects the operation ot the contiol valve in release is precisely as described in connection with the quick release operations. lfheii operating in graduated release chamber 28 is vented to atmosphere, as hereinbe- 'fore described, and valve c prevents air flowing from chamber 25 into port 98, so that emergency reservoir air cannot reach the seat of the release governing valve rlChe release of bralre cylinder pressure will be in direct proportion to the increase oi hralre pipe pressure in chamber 17 and the ratio of release willbe the same as the ratio of braking pressure resulting from a brake pipe reduction. A five pound increase et pressure in chamber 17 will result in a twelve and one-halia (12%) pound reduction et brake cylinder pressure betere the release valve is moved back to lap position. Brake cylinder pressure may thus be intermittently stepped down lrom a maximum service application pressure to Zero pressure. ln the release movements of the diaphragm structure it is immaterial what position the service valve takes. Said valve will move away from the service ports, and the extent of that movement is not important. This avoids the necessity et accurate and nice adjustments of the service valve. It is also true that the extent of movement ot the release valve in the service operations or' the diaphragm structure is immaterial. vThe release ports are moved out et register and the extent ot that movement is not important. r1`his avoids the necessity et' accurate and nice adjustments of the release valve, except, ot course, that both the lservice valve andthe release valve must be so positioned and adjusted that they will operate accurately and positively in performing their independent `functions.

Release after seMice-Graduated retention release (Fzg. 6).

rlhe control valve is adjusted for graduated retention release operationsby moving the release governing valve to retention release position, as shown in Fig. G. 1n this position ot the release governing valve cavityl places a port 119 in communication with the port 73. Port 119 is connected by passage 120 to a port 121 in the seat of the ing valve. The charging valve is ed .vitri a cavity 122 which in the chargposition of said valve connects port 121 a port 123. Port 123 is connectedby a passage 124e to the passage 114, this latter e leading to port 115 in the emergency sliue .'alve seat, as hereinbetore described. Cavity 112 is moved into position to connect port 37 with port 113. This permits brake cylinder pressure to tlow Y'trom chamber 18 through graduated release port 71, passage 86, port Y87, cavity 112, passage 114, port 115, cavity 116 of the emergency valve, port 117 and il' s je 113 into the retention chambor. ll'ralze cylinder pressure vwill also llow through the release port 70, passage 7 2, and fe through the restricted port 85 into 'We 75 and through the chamber 7`7'to e cylinder exhaust port 79.. So long as the charvne valve remainsin either one et' its charging positions, brake cylinder pressure may flow 'from passage 111 through passage 12a, cavity 122, passage 120, and cavity 7 i to the port 73 and thencethrough the restricted port 85 to atmosphere, as d elee scribed. Se lone as the valve c remains in release position and the charging valve remains in charging position bralre cylinder pressure will slowly build up in the retention chamber and will slowly blow down through the restricted poit 85. rl`he longer these valves remain in the positions indicated the greater fill be the development ot pressure in the retention chamber. lVhen the release valve is moved to lap position the charging valve will remain in charging position. nfhis will permit the pressure in the retention chamber to slowly blow down to atmosphere, so that it the release valve be held in lap position ier any considerable period, depending upon theV size and capacity el" dae ports, all ot' the pressure in the retention chamber 'will blow down to atthe brakes, or tor the purpose ot increasing brake cylinder pressure, the diaphragm 22 and the charging valve CZ will move downward and close communication between portsV 121 and 123,' thus trapping any pressure iin iso

ewa

built up at a ratio higher than the standard *Y two and .ene-half tor one.. (1) ratio. This is so 'because the developed brake cyl# inder pressure in chamber 18 must be high enough to overcome the upward force exerted on diaphragm by the pressure retained in the retention clnunbcr 1S). This will result .in va higher brake cylinder pressure` than would be necessary to move the' service valve to lap position-if there were no pressme inthe retention chamber. The operation of effecting a release of brake cylinder pressure, with the release governing valve in retention release position, is preciselyjas described under .the heading Release after service-Gradnated release. The n'iovement of the release governing valve to retention release position merely effects the building up of pressure in the retention chamber and the rel-Wee -of said 'pressure 'to atmosphere. y Y

The release governing valve is movedwto retention release position when it is desired to build lup a high brake cylinder pressure during cycling operations lwhen thefap'plication and release operations follow each other closely. This Aoperation of the brakes is necessary when running a train equipped with the ordinary` standard TWestinghouse freight brakes down along grade. 1n the manipulation of Vthese standard llVestingf house brakes it is necessary to resort to the kcycling methed of operation, )and itis also neces ary to use manually adjustable loaded retaining valves'.

Emergency application (Fig/.f1 V)1. Anemergency application is obtained Vby making a brake pipereductionV suliici'ently rapidso that pressure 1n chambers 1 and 10 cannot be reduced through groove 35 as rapidly as the brake pipe reduction in'. chainber 4.' This rate-of brake pipe reduction must be much more rapid than a service brake pipe reduction. Port 43isv of such capacity that the pressure in chamber 10 cannot be reduced at an emergency rate.

The result will be that the'pressure in the quick action chamber 10 will be vsuflicient to move piston 3 toward the left compressing the emergency springj125J The rib 126 on the piston will be forced into engagement with the gasket 127 and therchamber 1 will be sealed from the brake pipe passage 34. The piston 3 will pass beyond the port and passage 38 and thereby prevent the passage of quick action reservoirair from chamber 1() around the piston L3 into chamber 1. The piston 3 will moveiintoposition between the ends of the emergency 'groove 128 so that air may flow through said groove freely from chamber around the piston into chamber V1. i

The reduction lof pressure in chamber 1 results in an immediate reduction of pressure in chamber 17, andthe then undisturbed emergencyV pressure in 'chamber 2O forces the diaphragm structure upwardly'- and places the service valve inservice position; This unseats the checkvvalve 66 and v per,-

mits brake pipe air and brake pipe reservoir air-tor flow vto the brake cylinder before the emergency reservoir air has Abeen released into the yquick action v'chamber 10. The first pai-tof the movement of the piston 3 unseats the'poppet valve 129, saidvalve being conL nected by a( pin 130 to the valve stem '6, said stem being connected to the piston 3, as here` inbefore described. When thev poppetvalve is uns'eated.y portv 129 'is opened, said port leading from' the chamber '1 to the seat of the emergency slide valve. vPivotally mount'- ed in the chamberl() is an einergencyfvalve lever 131..V One end of this lever extends into a slot in the stop extension 36 of the piston 3.- There is a` lost motion between the end walls of s'aidfslotand the-,endofthe lever so that the piston may have'a short preliminary movement before the 'lever is vengagvged and'moved onits pivot. yThe other end of thelever 131 is in position to engage .and unseat an emergency' check valve .132, said valve being pressed to its seat' by a spring 133. Check valve 132n0r1nally closes a passage connecting a chamber 134 tothe quick action chamber 10. Chamber 134 is connect-'- ed bya passage 135l to the yemergency reservoir passage 60, and in said passage 135 is a. check valve 136 which seats toward the emergency reservoir and prevents air pass; ing from chamber 134"to said reservoir. This check valve, however, y,permits air to flow from v.the reservoir into the chamber 134,. The movement of the piston 3 to emergency position unseats the check valve 132 and permits emergency reservoir air to flow 'int-o chamber 10 and then around the piston through groove 128 into chamberl. The movement of the emergency valve a to emergency .position uncovers yemergency portf137 lwhich is connected by passage 138 to the brake cylinder pressure chann ber 18 so that. emergency reservoir air may flow direct from Vchamber 1 into cham# ber 18 and thence to the brake cylinder In the passager138is arrangedA a non-,return check valve 139 which prevents air flowing from chamber 18 to the seat ofthe emergency valve. When the lemergency slide valve is in emergency position port 129a registers with port 140 and this port is connected by a passage 141 to a chamber'142. `In this chamber is arranged an emergency vvent valve piston 143 which is connected by a suit'- able stem to the emergency brake 'pipe vent valve 33. This valve is normally held seated by a spring 144 and is arrangedin chamber 32. As hereinbefore described, chamber 32 poppet valve 129.

is connected directly to the brake .pipe C. The. emergency brake pipe vent valve 33 controls communication between chamber 32 and a large atmospheric port 145. When the port 129l registers with pert 14() high pressure emergency air flows fromchai'nber 1 into chamber 42 and forces upwardly the piston 143 there-by unseatiug the valve and connecting the chamber 32 and the brake pipe to thev atmospheric port 145 thusventH ing the brake pipe direct to atmosphee. From chamber.' lltheremergency air will flow direct to the brake. cylinder. y

` From chamber 1 the emergency reservoir air will flow through pas-sage 44 into the actuating chamber 17, and vtlrgough Vpassage 45 into chamber 31 oit the release governing valve. In the emergency position -ot the emergency valve ci a. portv 146 will register with port 117 and permit air to flow 'trom the chamber 1 .into said port 11.7 and through Ypassage 118 intotheretention chamber 19 so that the highemergency pressure .will ecpial ize in chambers 17, 18, and 19. A port'147 will connect port49 to an atmospheric port 148 so thatchamber 24 will be vented to atmosphere through passage port 49, port 147 and atmospheric port 148. The result of this will be that the brake pipe reservoir pressure in chamber 23 will 'torce the.

diaphragm 22 downwardly and thereliiy move the charging valve downwardly Vand close all of the charging ports as shown in Fig. 7.

Theport 146, in the emergency position of the emergency slide valve c will connect chamber 1 to a portand passage 149. said passage leadino to passage 104. As herein-- before described, passage 104 leads tc the emergency reservoir chamber V2t) ot the diafphragm structure. By this meansthepressure in chamber 20 will be equalized with the pressures in the other `chambers of the diaphragm structure. The piston 143 is provided with a small leak port 143a lto pern'iit the pressure in chamber 142 to slowly leak down to atmosphere after the. poppet. valve 129 has been seated, as will be hereinafter described.

Y Emergency Zap position (Fig.

valve 66 to its'seat and partially close the'A service ports 62 and 63. The service lap spring 150, shown in Fig. 10, will completely lap the service valve ports after an emergency application.

Uponv an equalization oixpressures in chambers 1 and 10 the vemergency spring 125 will move the piston 3 slightly, seating the l This slightindependent movement of the piston 3 is permitted by the pin-and-slot connection between the main lvalve stem 6 and the supplemental piston 5.

Piston 5 will be held seated againstV the gasket 127 by the high pressure in chamber 1 and said piston will resist Afurther move!A the .emergency lap condition. The lever 131 will hold the check valve 133 slightly open so that emergency reservoir air may slowly i'iow into chamber 10. The lost motion connection between the emergency valve a and the main valve piston stem 6 will permit of this emergencyflap movement of the main piston without moving the emergency slide valve onits seat to' any material extent.

Release after emergency.

A release after an emergency application is broughtabout by an increase in brake pipe pressure in the usual manner. pressure in chamber 4 must be raised above the pressure in chamber 1. This increase in pressure in chamber 4 will force the piston 5 inwardly and said piston, ai'ter a sho-rt movement, will pick up the main .piston stem and force the main piston 3 and the main slide valve inwardly to normal position and bring the stop stem 36 against its rigid stop. The checlrfvalve 132'will first be seated to close vcommunication between chamber 10 and the emergency reservoir. Air will tlow through groove 35 from chamber 4 -into chamber 1 when the piston 5 has moved inwardly beyond the entrance toV said groove. In the rnormal position ot the emergency slide valve a port 147 will connect port 140 to'V atmospheric port 143. This wilhvent chamber 142 to atmosphere and make certain that the valve 33 will seat. Air from The chambers 1 and 2 will How throughpassage r 44 into the actuating chamber 17 and move th-e diaphragm structurel downwardly thereby placing the release valve c in release position. The port 49 will be uncovered and air willvilow from chamber 1 into chamber 24,'and as the pressure-builds up insaid chamber the charging valve will be moved to charging position, as hereinbeitore Ydescribed, either in Vquickv release, rgraduated release, or retention release depending upon the posit-ion'otA the release vgoverning valve.

l/Vhat we claim is: 1. A control valve for airbrake apparatus comprising a service valve subject to brake pipe, brake cylinder and emergency reservoir pressures and operating upon -a reduction of brake pipe pressure to` place a source of braking pressure in communication with tlie brake cylinder for a service application of the brakes, tlie brake cylinder pressure assisting tlie brake pipe pressure lin moving the service valve toV lap position, a slide valve, and means operating upon an emergency reduction of brake pipe pressure to move the slide valve to emergency position and to connect an en'iergency reservoir to tbe sli-de valve chamber, said slide valve in emergency position `opening an emergency port to admit tlie'V emergency' reservoir air to the brake cylinder tor an emergency application of the brakes. Y l l 2. A control valve for air brake apparatus comprising a service valve'subject to Vbrake pipe,brake cylinder and emerge cy reservoir pressures and operating upon a reduction or" brake pipe pressure to place a source of braking pressure in communication witli the brake cylinder for a service application ofthe brakes, the brake cylinder pressure assisting tlie brake pipe pressure in moving` the service valve to lap position, a slide valve,'means operating upon an emergency reduction of brake pipe pressure to move tlie slide valve to emergency position and to connect an emergency reservoir to the slide valve chamber, said slide `valve in emergency position opening an emergency port to admit tlie emergency reservoir air to the brake cylinder' for an emergency applicationoi tlie brakes, means operating Wlieny tlie emergency valve is in emergency position to close communication between the service valve andA the brake pipe, and means controlled by the slide valve and operating when tlie said slide valve is in emergency position to vent the brake pip-e to atmosphere.

3. A control' valve for air brake apparatus comprising a service valve subject to brak pipe, brake cylinder 'and emergency reservoir pressures andoperating upon a reductionof brake pipe pressure to place the brake pipe and a brake pipe reservoir in 'communication Vvvitli tlie brake cylinder for al service application of tlie brak-es, tlie brak-e cylinder pressure assisting tlie brake pipe pressure in moving` tlie service valve-to lap position, a slide valve, and lineans operating upon an emergency reeuction of brakev pipe pressure to move the slide valve to emergency position and to connect an emergency reservoir to tlie slide valve chamber sair 'slide valvein emergency position opening` an emergency port to admit the' emergency reservoir air tothe brake cylinder 'for anfemergency application of tlie brakes.

l, A control valve for air brake apparatus comprising a service application valve and a separate release valve subject to brake pipe, brake cylinder and emergency reservoir pressures, the service valve operating upon a reduction of brake pipe pressure to place a' source of braking pressure in communica- Vduction cit brake pl tion withv the brake cylinder for a service application of tlie brakes, the brake cylinder release valve operating upon an increase of brake pipe pressure to place the brake cylinder .in communication with atmosphere;

and means operating upon an emergency repressure to connect an emergency reservoir to the brake cylinder independently oi the service valve for an emergency application oi the brakes.

5. A control valve lor air brakeappara-tus conipri a servico application valve and separate release 'valve subject to brake pipe, brake cylinder and emergency reservoir-pressures, .tlie service valve operating upon a reduction-of brake pipe pressure to place a brake pipe and a brake pipe reservoir in communication WithV tlie brake cylinder for a serviceapplication of the brakes, the braker cylinder pressure assisting the brake pipe pressure in moving .the service i valve to lap position, the release'valve operating upon an increase of brake pipe .pressure to place tl'iebrake cylinderv in coin- A.munieation willi. atmosphere; and means operating upon an emergencyreduction of brake pipe pressure to connect an emergency lreservoir to the brake cylinder independently of tlie service valve for an emergency application of the brakes.

G. A control'valve for air brake apparatus coii'iprising a service application valve and a separate release valve botli valves subject to brake pig-pe, brake cylinder and emergency reservoirpressures, tlie service valve operat- Ving upon a reduction of brake pipe pressure to place a brake pipe and al brake pipe reservoir in communication vvitli the brake cylinder for a servicev application of the brakes, the brake cylinder pressure assisting the kbrake pipe pressure in moving tlie .service valve to lap position, tlie release valve operating upon an increase of brake pipe pressure to place tlie brakecylinder in communication Witli atmosphere'.

7. A control valve for brake apparatus comprising a service application valve and a` separate release valvel subject to brake pipe, brake cylinder and emergency reservoir pressures, tlie service valve operating upon a'reduetion of brake'piperpressure to place a source of Abraking pressure in communication Willi the brakev cylinder for a service application of tlie brakes, the brake cylinder pressure assisting the brake pipe L in moving lie service valve to'lap position, the release. valve operatingupon an igcrease of brake pipe pressure to yplace the brake cylinder in communication With atmosphere; means operating upon an emergency reduction of brake pipe pressure toy connect van emergency reservoir to tlie brake cylnider independently of the service lvalve for an emergency application of the brakes; 'and means opei'ated by an inciease of brake pipe piessure to exhaust the emergency reservoir pressure troni the release valvestructure to permit the brake pipe pressure to quickly and positively move the release valve to release position.

8. A control valve' :for air brakeapparatus comprising a service application valve and a separate release valve both valves subject to brake pipe, brake cylinder and emergency reservoir pressures, the service valve operating upon a reduction of brake pipe pressure to place a source of braking pressure in con'imunication with the bi'ake cylinder for a servire application of the brakes, the brake cylinder pressure assisting .the brake pipe pressure in moving the service valve to lap position, the release valve operating upon au increase ol" brake pipe pressure to place theV brake cylinder in conin'iunication with atmosphere; and means operated by an increase oi' brake pipe pressure to exhaust trie emergency reservoir pressure romtlie release valve structure to permit the brake pipe pressure to quickly and positively nieve the release valve to release position.

9. control valve for air brake apparatus comprising a service applieirion valve and a separate release valve botti valves subject to brake pipe, brake cylinder, and emergency reservoir pressures, the service valve operating upon a reduction of brak-e pipe pressure to place a source of braking pressure in communication with the Vbrake cylinder for a service application of the brakes, the brake cylinder pressure assisting thebitake pipe pressure in moving the service valve to lap position, the release valve operating upon an increase of brake pipe pressure to place the brake cylinder in communication vwith atmosphere; means operated by an increase o'j brake pipe pressure to eX- liaust the en'iergency reservoir pressure from the release valve structure to permit the brake pipe pressure to quickly and positively move the release valve to release position; and manually operable means to render said exhaust means operative or inoperative. y

1072i control valve Al'or air brake apparatus comprising a brake cylinder' rrelease valve subject to brake pipe, brake cylinder and emergency reservoir pressures and 0perating jupon an increase oif brake pipe pressure l'orplace the brake cylinder' in communication vfil'li an exhaust port for a release el: the, brakes, the emergency i'eservoir pressure opposing the brake pipe pressure and Vtending to move the release valve to lap position, and means operated by an increase of brake pipe pressure to exhaust the emergency reservoir pressure from the release valve structure to permit the brake pipe pressuieto quickly andpositively move thei release valve ,to release positionr.

A1l. control valve for air br ratus comprising a brakecylinder release valve subject to brakeipipe,`brake cylinder 2e appaand emergency reservoir pressures and op- Y erating upon an increase Vof brake pipepressure to place the brake cylinderiin communication with anV exhaust portl for a release oi the brakes, the emergencyY reservoirpiessure opposing the brake pipe pressure Vand tending 'to move the release valve to position, means operated by anincrease of brake pipe pressure to exhaust .the 'emergency reservoir pressurey from the release valve structure to permit the brakepipe pressure to quickly and positively.l move the release valve to release position, and man ually operable means to render,said'exhaust means operative or inoperative.

l2. i tluid press refbrake control valve operating upon a reduction of brake pipe pressure to admit air to the brake cylinder VAfor an application of the brakes and op.- iiating upon an increase in brakeY pipe pressure to connect the brake cylinder tofatmospliere, and provided vrith a release-governing valve having a graduated-release position and a quick-release position, a service valveoperatinfr means consist-ing of 'an actuating diaphragm, an equalizing diaphragm, an emergency diaphragm, an aetuatinei cham` ber :in communication Vwith the brake pipe, a brake cylinder pressure chamber between the actuating` diaphragm and tlieequalizing diaphragm and in communication with the brake cylinder, a retention chamber between the eque-lining diaphragm and tlievemergency diaphragm, and an emergency reservoir chamber in communication with the emergency reservoir, a service valve operativelyV connected to said diaphragnis and Vin its application position admitting airv tothe brake cylinder and to the saidV brake 'cylinder pressure chamber, a release valve operatively connected to the service valveoperating means and in its release position admitting brake cylinder pressure into the said retention chamber and in its lap po- Y sition closing vsaid communication, and means to permit the pressure inthe retention chan'iber toslovvly blow down to atincs-V Y pliere Without regard to the position olthe said release valve and the said service valve.

131A Y[luid pressure brake control vaflve operating upon a slow` reduction of brake pipe pressure to admit air to the brakejcylr inder 'lor a service application of the brakes and-operating vupon a sudden'vreduction et brake pipe pressure to admit emergency reservoir air to the ,brake cylinder Jier an emergency application ot' the brakes and operating upon an increase invbrake pipe pressure to connect the brake cylinder to atmosphere, and provided with a release-governing valve Vliaust of brake 'cylinder pressure and in its graduated-release position closing said full and free eXliau-st, a quick-release control valve, means controlling communication between the emergency reservoir and the brake pipe, means whereby an increase `in brake pipe pressure 'tor a releaseot tiie `brakes Wili open said quick-release control valve. to permit emergency reservoir air to floivto tbc brake pipe, said means thereafter automatically closing vsaid quick-release control valve during' the rise'oil brake pipe pressure, and.'l means. Wliereb-y tbe release-governing valve in. its graduated-release position Willprevent the opening oir the quick-reiease control valve, said release-governing valve in its quick-release position permitting tlie opening of sai-cl quick-release control valve!v l 14. A control valve for air brarlreappa-ratus comprising y .service valve su-bjzectv to` brake pipe, brake cylinder and emergency reservoir pressures and operating' upon a reduction of. brake pipe 'pressure t'oplaceV a source or' braking pressure incommunication Witli the brake cylinder Ytor a service appl-ication of the brakes, tlie brake cylinderpressure assisting the brake pipe pressure v in moving the service valve to lap position, `a slide valve, means opera-ting. upon an ,ei-nergency reduction oft brake pipe pressure rt .move tlie slide. valve to emergency position and to connect an emergency reservoir to tlie slide valve chain-ber, s-aid slide. valve. in emergency position opening an emergency port to` admit tlie emergency .reservoir to the brake cylinder for an emergency applicationV of the brakes, and a charging valve-subject to brake pipe press-ure and. tothe pressure from abialre pipe reservoir and operating to charging position upon` an increase of brake pipe pressure to connectv tlie bralre pipe to! the brake pipe rreservoir and tothe einergency reservoir. Y

. l5.. An air brake appara-tuscoinprising a brake pipe,'a bralre pipe reservoir, an. einergency reservoir, a service valve subject to brake pipe, brake cylinder and emergency reservoir pressures andi operating upon a reduction of brake pipe pressuretol place the bralre pipe and the brake pipe reservoir in commi-inication with the brake cylinder for a service application of the brakes, tbe brake cylinder pressure assisting tlie` bra-lie pipepressure ini moving' tlie service valve to lap position, a slide valve,.ineans operating upon an y emergency reduction of brake pipe pressure to move the slide valve to emergency position. and toconnect an emergency reservoir to-tlie slide valve cli-amber, said slide valve in emergency position openingan vemergency port to admit the emergency reservoir air to tlie bra-ke cylinder for an emergency application of the brakes, and means to, prevent tl'ie brake pipe reservoir pressure'reducing with tl'ie brake pipe pressure uponf'a brake pipe. reductionifor an application. of the brakes. f Y

lo, An air brake apparatus comprising a brake pipe7 a brakepipereservoir, anlemer.-

gency .reservoir7 a service valvesu'bjeet' to.y brel-:e pipe, brake `cylinder and emergencyy reservoir lnessures and operatingfupon a reduction lbrake pipe pressure. to place the brake pipe and the brake. piperres'ervoir in.

communication with the brake cylinder for. aY

service'appiication of tlie brakes, tl'ie brake:

rcylinder pressure-assisting the brakevpipe pressure in moving the service valve talap positioin. and means to prevent the brake:V

pipe reservoir pressure reducing ,Wiftl'il` brakel pipe' pressure upon a brake pipereduction for an application of the brakesil,

17.7An air braille apparatus comprising a;

brake pipe, ai brake pipe reservoir,I air emer-` gency reservoir, a service valve. subJectto brake pipe, brake cylinderl and emergency reservoir pressures and operating upon a reduction orv brake pipe pressurev to placer-talliebrake pipe and the brake pipereservoirin communication with. tllie brake Acylinder for a service application of the bra'kes,tlie. brake cylinder pressure assisting rthe brake.pipey pressure in moving the service valve tor lap position, means whereby the service valve in; moving to. service position will first place the.-v

bralre pipe in communication with. tlie brake cylinder and Will-then. place botlitlieb-rake pipe and the brake pipe reservoir incominunication With/the brake cylinder, and means to prevent the brake pipe reservoir. pressure' reduc-ing with brake pipe pressure uponl a brake pipe reduction for anl application of. the brakes. Y f. i

18. A control valve for air brake. apparaitus comprising a service Valve subjiect tor brake pipe, bralre cylinderl and emergency reservoir pressures and operating upon areduction of-brake pipe pressi-rre toplace a source of braking pressurein communications with `the bra-ke cylinder for a service application of tlie brakes, the brake cylinder pressure assisting the brake `pipe pressure in moving the service valveto. lappositionp ai charging.' valve subject toj brake pipe. pressure. and toI the pressure from a brake pipe. reservoir and' operating. toI normal charging position. upon an increase ot brake pipe. pressure at normal charging. rate tor connect the brake pipetotlie brake pipe reservoir and to tlie emergency reservoir, andoperating to. non-overcbarge position'upon excessivey increase of brake pipe lpressure above the! normal. chai-ging rate to close` communication. ivitlrtlie emergency reservoir,` and meansI operating ivlien the charging; valve isf in nonel overcliarge position to restrict the release oii brake cylinder exliausti Y l. 1

iis

iso

19; A control valve for air'brake apparatus comprising'a service valve subject to brake pipe, brake cylinder and emergencyreservoir'pressures and operating upon afreduc- 1 tion of brake pipe pressure to place "a source operating to normal charging positionv upony an increaseof brake pipe pressure at normal charging'rate and operating to non-over-l charge position upon excessive increase or brake pipe pressure above the normal chargingv rate; and means operating ywhen the charging valve is in non-evercharge position to restrict the release of brake cylinder ez;- haust.

20. A control valve for air brake apparatus comprising a service valve subject to brake pipe, brake cylinder and emergency reservoir pressures and operating upon a reduction of brake pipe pressure to place a source of braking pressure in communication with the brake cylinder tor a service application of the brakes, the brake cylinder pressure assisting the brake pipe pressure in moving the service valve to lap position, a charging valve subject to brake pipe pres'- sure and to the pressure from a brake pipe reservoir and operating to normal charging position upon an increase otbrake pipe pressure at normal charging rate, and operating to non-overcharge position upon excessive increase of brake pipe pressure above the Y normal charging rate, a normally openrelease restricting` valve, and means operating when the charging valve is in non-overcharge position to close said release restricting valve to restrict the release ot brake cylinder exhaust.

'21. A control valve for air brake apparatus comprising a service valve subject to brake pipe, brake cylinder andV emergency reservoir pressures and operating upon a reduction of brake .pipe pressure to place a source or breaking pressure in eomniunicationA vvith the brake cylinder for a service application of the brakes, the brake cylinderl pressure assisting the brake pipe pressure in moving the service valve to lap position, a charging valve subject to brake pipe y pressure and to the pressure from a brake pipe reservoir and operating to normal charging position upon an increase oi brake pipepressure at' normal charging rate and operating to non-overcharge position upon an excessive increase of brake pipe presssure above the normal charging rate; a quick release control valve closing communication between the emergency reservoir and the brake pipe, means operating 'when the chargrescues ing valveV isin either charging or non-over-v charge position toV move theV quick releasev control valve to open communication f'between the emergency reservoirand the brake pipe; and means operating When the charging valve 1s in non-overchargeposition to restrict the release of brake cylinder ex-V voir pressures and operating upon reductionfot' brake pipe pressure toplace a source ot braking'pressure 1n communication with the brake cylinder for a service application of the brakes, the ybrake cylinder-pressure.

as isting the brake pipe pressure in movingthe service valve to lap positioma charging valve subject to brake pipe pressure and to the pressure from a brake pipe'reservoir and opera-ting to charging positionv upon an 'increase or bra-ke pipe pressure, 'a quick release control valve normally closingcommunication between the emergency r servoir'and the brake pipe, and means operating when the charging valve is in charging yposition to move the quick release control valve to open communication bet-Ween thel emergency reservoir and the brake'pipe.

23. A control valve for air-brake apparatus comprising a service valve operating upon a reduction of'brake pipe pressure to place a source or braking pressure incommunication With the brake cylinder for a service application ot the brakes,'a charging valve subject to brake pipe pressure and operating the charging position upon an increase ot' brakepipepressrn'e, a quick release control valve normally-'closing communication between `an emergency reservoir and the brake pipe, and means operating when the charging valve is in. charging position to move the release control valve to open communication between the emergency reservoir and the brake pipe.

2a. A control valve Jjor air brake apparatus comprising aservice valve operatingupon reduction of brake .pip-c pressure to place a source or braking pressure in communication with the brake cylinder for a service application of the'brakes, a charging valve subjectA to brake pipe pressure and operating to normal charging position upon au rincrease ot'brake pipe pressure at normal charging rate and operating to nonovercharge position upon an excessive increase o'f brake pipe pressure above the normal charging rate; a quick release control valve norn'ially'closing -communication between an emergencyreservoir and the brake pipe, means operating When the charging valve is in either charging, or non-over'- charge position to move the release control valve to open communication between the emergency reservoir and the brake pipe; 

